> You quoted Klaus as saying:
>
> >> The conventional s-curve of silver halide emulsions is
> >> WRONG and it remains wrong no matter how carefully one
> >> reads Ansel Adams' books or any other publication on
> >> silver halide sensitometry....
>
> One thing that did come out of that discussion was that Klaus and Kuehn
> were both wrong in terms of modern materials. This is on the assumption
> that we are talking of the amount of information that can be got onto the
> negative and onto the paper. Peter Marshall said that one could print more
> than the eye can see onto silver gelatine paper. Then I disagreed but it
> has been demonstrated to me since that I was wrong. The practical
> demonstration was achieved through a combination of exposure and
> development of the negative so that it would print onto the silver gelatine
> paper without masking or digital manipulation. Whether one wishes to print
> more than one can see is a matter of choice and objective. For
> architectural record one may wish to do so but if one wishes to record what
> one saw,given the limitations of the pupil and the retina, in terms of
> atmosphere and feeling then such a range of tone and detail could, and
> probably would, be quite inappropriate.
>
>
> You also say::
>
> > 1. Better separation of tones in shadows and highlights, in order to
> compensate for the compression of these values that is inherent in the
> long,
> flat shoulder and toe of the Pt/Pd D/LogE curve;
> <
>
> Is the fact that one can obtain good separation of highlights and shadow
> detail in Pt/Pd prints from in camera negatives with a density range of
> over 2, by controlling the exposure and development of the negative and the
> mix of the sensitiser, at variance with what you say,or are we just using
> different means to achieve the same objectives ?
>
> Can I say again how grateful I am for such a constructive contribution.
>
> Terry King
>
It seems to me, and I must add that I have had the opportunity to see
several of Charlie's prints, which were very vibrant and luminous, that
he is eliminating the compression and compaction of tones inherent in the
toe and shoulder of the response curve. This would, of course, increase
separation in the shadows and highlights resulting in a print whose
appearance could not be duplicated by variations of exposure vs. development.
Thanks, Charlie, for your postings.
John
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